The chandeliered, mosaic-covered vestibule in central Moscow's Kurskaya station now bears a line from an old version of the Soviet national anthem: "Stalin brought us up to be loyal to the nation, inspired us to labor and great deeds."

The leader of the small, pro-Western opposition party Yabloko called on the Russian president to remove the words, calling them a "violation of the memory of the millions of victims from Stalinism."

"There is no way that restoring this station to its original look can be justified," Sergei Mitrokhin said on his party's site yabloko.ru.

For the head of human rights group Memorial, Oleg Orlov, the inscription "gives an open and imprudent signal to the full rehabilitation of Stalin," he was quoted as saying on the kasparov.ru site, run by staunch Kremlin critic Garry Kasparov.

Though millions of Soviets perished during Stalin's rule in gulag labor camps or from famine, the dictator is still revered by many Russians for defeating the Nazis in World War II.

Last year, Stalin, who opened the Moscow metro in 1935, was voted Russia's third most popular historical figure in a poll run by state television channel Rossiya.

On news site infox.ru, a spokesman for the Moscow metro defended the restoration: "We always strive to work in a way that optimally restores something to its original state.

"It had the same inscription back then, too," he said of the station, built in 1950.

The words were penned by the poet Sergei Mikhalkov in 1944, who died on August 27 aged 96.

In 1956, three years after Stalin's death, his successor Nikita Khrushchev denounced the Soviet Union's most notorious leader at a Communist Party congress and a campaign was launched to erase monuments and references to him.

Five years later, Khrushchev removed Stalin's body from the mausoleum in Red Square where he lay beside Soviet founder Vladimir Lenin and buried him by the Kremlin wall.

On August 27, a member of the Moscow parliament said it had not given approval to the metro to go against Khrushchev's 1956 law, which he said was still in place.

"We should be guided by the legal issue that no one has canceled these documents," Ekho Moskvy radio quoted Mikhail Moskvin-Tarkhanov as saying.